In 1976, in his first run for public office, Hatch was elected to the United States Senate, defeating Democrat Frank Moss, a three-term incumbent. Among other issues, Hatch criticized Moss' 18-year tenure in the Senate, saying "What do you call a Senator who's served in office for 18 years? You call him home."[5] Hatch argued that many Senators, including Moss, had lost touch with their constituents.[6] Hatch himself has now been in office for 40 years.

Hatch has been a longtime advocate of amending the United States Constitution to require that total spending of the federal government for any fiscal year not exceed total receipts.[8][9] He proposed the DREAM Act, which would provide a pathway to citizenship for the children of undocumented immigrants, who were children when their parents came to the United States.[10]

Senator Hatch co-sponsored the Restoring the 10th Amendment Act (S. 4020 111th Congress), which would strengthen state rights under the 10th Amendment. The bill would provide special standing for state officials in challenging proposed regulations.[11]

In 2018, Hatch announced that he would retire after seven terms in the Senate.[12]

In 2000, Hatch made a failed bid for the Republican presidential nomination, losing to then-TexasGovernorGeorge W. Bush. During the first Republican debate, Hatch made web usability a campaign issue, a first for a presidential candidate. He claimed his website was more user-friendly than Bush's. At least one web usability expert agreed.[16]